org.djunits.unit

Class AbsoluteLinearUnit<AU extends LinearUnit<AU>,RU extends Unit<RU>>

java.lang.Object

org.djunits.unit.Unit<U>

org.djunits.unit.LinearUnit<AU>

org.djunits.unit.AbsoluteLinearUnit<AU,RU>

Type Parameters:

AU - the absolute unit.

RU - the corresponding relative unit

All Implemented Interfaces:

Serializable, AbsoluteUnit

Direct Known Subclasses:

AbsoluteTemperatureUnit, DirectionUnit, PositionUnit, TimeUnit

public abstract class AbsoluteLinearUnit<AU extends LinearUnit<AU>,RU extends Unit<RU>>
extends LinearUnit<AU>
implements AbsoluteUnit

An absolute unit is a unit that needs to be defined with a "distance" to the reference absolute unit. E.g., for Time, an absolute reference unit has to be chosen such as an Epoch (e.g., 0001-01-01 AD at 00:00), where other TimeUnits can be defined relative to that reference unit (e.g., POSIX time, 1-1-1970 at 00:00, which is 719162 days after the reference time).

An absolute unit is always a unit with an OffsetLinearScale. The offset defines how far away the origin of that absolute unit is compared to the base unit. The linear scale indicates in what default "steps" compared to the reference relative scale the absolute scale is used. For temperature, this is very clear. Degrees Celcius is shifted 273.15 compared to the origin of the Kelvin scale, and the linear unit is 1 (relatively, 1 Kelvin is one degree Celcius). For Degree Fahrenheit, the linear scale is 5/9, and the offset is 459.67. For Direction, North can be chosen as 0, and radians (SI) as the default angle. But one could also define a NORTH_DEGREES absolute direction unit, or a WEST_RADIANS one. Similar choices can be made for time and position.

Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
BSD-style license. See DJUNITS License.

$LastChangedDate: 2015-07-24 02:58:59 +0200 (Fri, 24 Jul 2015) $, @version $Revision: 1147 $, by $Author: averbraeck $, initial version Apr 27, 2017

Author:

Alexander Verbraeck

See Also:

Serialized Form

Field Summary

Fields inherited from class org.djunits.unit.Unit

STANDARD_UNITS

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbsoluteLinearUnit(String name, String abbreviation, UnitSystem unitSystem, double scaleFactorToReferenceUnit, double offsetToReferenceUnit, RU relativeUnit) Build a user-defined unit with an absolute linear scale and create the fields for that unit.
protected	AbsoluteLinearUnit(String abbreviationKey, UnitSystem unitSystem, double scaleFactorToReferenceUnit, double offsetToReferenceUnit, RU relativeUnit) Build a standard unit with an absolute linear scale and create the fields for that unit.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
boolean	equalsIgnoreNaming(Object obj) Test if two units are the same, except for the name and abbreviation.
double	getOffset() Return the offset to transform to the standard (reference) unit.
RU	getRelativeUnit() Return the corresponding relative unit that belongs to this absolute unit.
OffsetLinearScale	getScale()
int	hashCode()

Methods inherited from class org.djunits.unit.LinearUnit

getScaleFactor

Methods inherited from class org.djunits.unit.Unit

generateHashCode, getAbbreviation, getAbbreviationKey, getAllUnitsOfThisType, getDefaultLocaleAbbreviation, getDefaultLocaleName, getDefaultLocaleTextualRepresentation, getDefaultLocaleTextualRepresentations, getDefaultTextualRepresentation, getName, getSICoefficients, getSICoefficientsString, getStandardUnit, getTextualRepresentations, getUnits, getUnitSystem, isBaseSIUnit, isLocalizable, lookupOrCreateSIUnitWithSICoefficients, lookupOrCreateUnitWithSICoefficients, lookupUnitWithSICoefficients, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.djunits.unit.AbsoluteUnit

getScaleFactor

Constructor Detail

AbsoluteLinearUnit

protected AbsoluteLinearUnit(String abbreviationKey,
                             UnitSystem unitSystem,
                             double scaleFactorToReferenceUnit,
                             double offsetToReferenceUnit,
                             RU relativeUnit)

Build a standard unit with an absolute linear scale and create the fields for that unit.

Parameters:

abbreviationKey - String; the key to the locale file for the abbreviation of the unit

unitSystem - the unit system, e.g. SI or Imperial; often the unit system for an absolute unit will be OTHER

scaleFactorToReferenceUnit - double; multiply by this number to convert to the standard unit

offsetToReferenceUnit - double; the offset to the reference unit to add to convert to the standard (e.g., BASE) unit

relativeUnit - RU; the corresponding relative unit belonging to this absolute unit

AbsoluteLinearUnit

protected AbsoluteLinearUnit(String name,
                             String abbreviation,
                             UnitSystem unitSystem,
                             double scaleFactorToReferenceUnit,
                             double offsetToReferenceUnit,
                             RU relativeUnit)

Build a user-defined unit with an absolute linear scale and create the fields for that unit.

Parameters:

name - String; the unit name

abbreviation - String; the unit abbreviation

unitSystem - the unit system, e.g. SI or Imperial; often the unit system for an absolute unit will be OTHER

scaleFactorToReferenceUnit - double; multiply by this number to convert to the standard unit

offsetToReferenceUnit - double; the offset to the reference unit to add to convert to the standard (e.g., BASE) unit

relativeUnit - RU; the corresponding relative unit belonging to this absolute unit

Method Detail

getScale

public final OffsetLinearScale getScale()

Overrides:

getScale in class LinearUnit<AU extends LinearUnit<AU>>

Returns:

the scale to transform between this unit and the reference (e.g., SI) unit.

getOffset

public final double getOffset()

Return the offset to transform to the standard (reference) unit. Add this number before scaling to convert to the standard (e.g., SI) unit. For Degrees Fahrenheit, the offset is 459.67 to convert it to Kelvin, the standard unit.

Specified by:

getOffset in interface AbsoluteUnit

Returns:

double; the offset to transform to the standard (reference) unit.

getRelativeUnit

public final RU getRelativeUnit()

Return the corresponding relative unit that belongs to this absolute unit.

Returns:

the relative unit that belongs to this absolute unit

hashCode

public int hashCode()

Overrides:

hashCode in class LinearUnit<AU extends LinearUnit<AU>>

equals

public boolean equals(Object obj)

Overrides:

equals in class LinearUnit<AU extends LinearUnit<AU>>

equalsIgnoreNaming

public boolean equalsIgnoreNaming(Object obj)

Test if two units are the same, except for the name and abbreviation. This means for instance that for the MassUnits METRIC_TON and MEGAGRAM (both 1000 kg) equals(...) will yield false, but equalsIgnoreNaming will yield true.

Overrides:

equalsIgnoreNaming in class LinearUnit<AU extends LinearUnit<AU>>

Parameters:

obj - Object; the object to compare with

Returns:

true if the two units are the same numerically, except for the naming and/or abbreviation